DAX Studio Parameters Dialog
I recently updated the documentation on daxstudio.org to include a page on the Parameter Support, but I thought this might also benefit from a longer explanation.
It may surprise some people to hear this, but the DAX language has supported parameters in queries since it was first released. However while you can use parameters in a DAX query you cannot easily test parameterized DAX by supply the parameter values as variables like you can in T-SQL. In DAX the parameters are sent in a separate part of the XMLA as part of the XMLA command’s parameters collection. Historically one of the biggest issue with parameters in DAX (and MDX) has been the client tool support. From what I have experienced, they are really only used in Reporting Services reports. However with the addition of “paginated” reports to the PowerBI.com we may start to see a resurgence of these types of reports.